Objective　To investigate the effects of trace elements on the metabolism of extracellular matrix and explore the physiological and pathological mechanism of trauma. Methods　Based on the experimental and clinical data, it was studied that the action of trace elements in the metabolism of extracellular matrix in trauma repairing. Results　During wound healing, the trace elements were the components of many kinds of enzymes, carriers and proteins. They took part in the synthesis of hormones and vitamins as well as the transmission of information system. They activated many different kinds of enzymes and regulate the levels of free radicals. The trace elements had the complicated effects on the synthesis, decompose, deposition and reconstruction of collagen and other extracellular matrix. Conclusion　The trace elements play an important role in regulating the metabolism of extracellular matrix.

Objective　To investigate the repairing effect of transplantation of allogeneic fetal bone in combination with a covering cryopreserved periosteal allograft to bone defect. Methods　Twenty Long-eared white male rabbits were chosen as experimental model of bilateral 12 mm combined bony and periosteal radial defect. Cryopreserved allograft periosteum with allogeneic fetal bone were implanted in the left defect as experimental side and fetal bone was simply transplanted in the right defect as control side. Bone repair process in the two groups were compared by macroscopy, microscopy, roentgenograms and the contents of calcium and phosphate in the defect area at 2、4、8 and 12 weeks after transplantation. Results　There was significant statistic difference in the contents of calcium and phosphate between the experimental and control sides at 4、8 and 12 weeks after transplantation (P<0.05). With time passing by, the contents of calcium and phosphate have the increasing trends. In the experimental group, lamella bone was seen and medullary canal recanalized at 8 weeks postoperatively. The histological section showed the bone lacuna and lamella bone were formed. Conclusion　It suggests that allogeneic fetal bone in combination with a covering cryopreserved periosteal allograft can promote bone repair, and allogeneic fetal bone is excellent bone substitute.

Objective　To review the recent progress in the treatment of wrist disorder by limited intercarpal arthrodesis and the related experimental study. Methods　Recent original articles related to limited intercarpal arthrodesis, including clinical practice and experimental study, were extensively retrieved and carefully analyzed. Results　Limited intercarpal arthrodesis could relieve pain and stabilize the wrist joint with partial motion. Conclusion　 With suitable indication and well selected operation approach, the limited intercarpal arthrodesis should be the optimal surgical intervention than total carpal athrodesis in the treatment of wrist disorder.

Objective　To investigate the clinical results of the medial multiplex flap pedicled with the posterior tibial vessel. Methods　Twelve cases with soft tissue defects and bone defects of limbs were treated with the medial multiplex flap pedicled with the posterior tibial vessel from September 1992 to May 1999. Among them, bone and soft tissue defects following opened fracture in 7 cases, chronic ulcer following chronic osteomyelitis in 2 cases, melanoepithelioma in 2 cases, bone and soft tissue defects following osteoma resection in 1 case. The bone defect area was from 2.5 cm×5.0 cm to 4.5 cm ×11.0 cm. Free graft was performed in 5 cases, bridged transposition in 3 cases and reversal transposition in 4 cases, among them, periosteal myocutaneous flap with autogenous or allogeneic bone grafting in 8 cases, myocutaneous flap in 4 cases. The area of the flaps from 6 cm ×8 cm to 12 cm×25 cm. Results　All flaps were healed by first intention, but in the distal fragments of bigger flaps were partially necrosed in 2 cases. In 10 cases bone healing were obtained after 16 weeks of operation according to the X-ray photos. All cases were followed up from 6 to 18 months. All cases achieved satisfactory result but 1 case died because of lung metastasis of osteoma. Conclusion　The multiplex graft pedicled with the posterior tibial vessel is an ideal graft for repairing the large soft tissue defects and bone defects, because it has such advantages as adequate blood supply, big vascular diameter, long pedicle and big dermatomic area.

Objective　To investigate the factors which affect the bone union of distracted region after limb lengthening, so as improve the curative effect and diminish the incidence of complication. Methods　To look up the latest literatures dealing with the bone union in limb lengthening, then review the procedure of osteogenesis and the affecting factors. Results　The osteogenesis of distracted region after limb lengthening is a sophisticated procedure. It can be affected by the velocity of lengthening, the period of lengthening, the site and method of osteotomy, the age etiology of patient. Conclusion　The bone union of distracted region after limb lengthening can be facilitated by following factors :① the velocity of lengthening slower than 1.0 mm/day; ② moderate delay in distraction; ③ axial shortening of distracted region; ④ micromovement stimulation.

Objective　To manufacture adriamycin-porous tricalcium phosphate (A-PTCP) ceramic drug delivery system (DDS)as a possible method for bone defect treatment after bone tumor operation. Methods　A-PTCP DDS was made from putting adriamycin into PTCP. Thirty rabbits were divided randomly into group A(24 rabbits) and group B(6 rabbits). A-PTCP was implanted in the greater trochanter of the right femur in group A. Adriamycin were injected into veins in group B. Muscle around A-PTCP and plasma were taken out at different period. Adriamycin concentrations in muscle and plasma were measured by high performance liquid chromatography (HPLC). Results　A-PTCP could gradually release adriamycin over 10 weeks. Adriamycin concentrations in the muscle were higher than that in plasma. Conclusion　A-PTCP may be a new method for repairing bone defects after bone tumor operation.

Objective　To explore the influence of stress-relaxation plate(SRP) fixation on the remodeling of cortex under plate. Methods　Twenty-eight New Zealand rabbits were used in this study, the bilateral tibia were osteotomized in the middle and fixed with SRP (experimental group) and rigid plate (control group) respectively. The scanning electron microscopy was used to observe the bone remodeling process from 2 to 48 weeks after operation. Results　There was cortex osteoporosis beneath plate in different degree in both experimental and control groups before 8 weeks, it showed as the disorganization of collagen fiber structure and formation of resorption cavities. In comparison, the osteoporosis degree in experimental group showed milder than that of the control group. After 12 weeks, the resorption cavities became smaller, and the structure of collagen fibers became regular with the alignment parallel to the long axis of cortex. In contrast to the experimental group, the bone osteoporosis under plate of control group exacerbated continuously. Conclusion　Without removal of the bone plate, SRP fixation not only reduce the degree of plated bone osteoporosis, but also make the osteoporosic bone return to normal.

Objective　To investigate the feasibility of osteoid callus allograft as a kind of bone healing promoting materials. Methods　The osteoid callus was obtained at one week after bilateral femoral fracture of a SD rat, then was kept at -196℃ for 2 weeks. The bone defect model which bone repair was in intra-membranous osteogenesis was made at bilateral tibial shaft in 5 rats, and filled with the osteoid callus in the left defect area, the right side was filled with allogenous cancellous as control group. The specimen were processed with undecalcified technique and the sections were staining with light blue and sofranin T. Results　After 2 weeks ,there were cartilage and bone formation in the defect area of osteoid callus graft group(3/4), medullary cavity formation in bone tissue with cartilage arround it, fibrous tissues between new bone and host bone. While there were no cartilage or bone formation in the control group. Conclusion　The allograft osteoid callus is not absorbed by immunological rejection, but changed into bone tissue through endochondral osteogenesis. It is inspiring to develop osteoid callus allograft as a kind of material for bone healing.

Objective　To prevent early closure of growth plate and developmental deformities of limbs by allografts of cultured cartilages into growth plate defects of rabbits. Methods　Chondrocytes isolated from articular cartilage of 1-month rabbits formed cartilage after cultivation in centrifuge tubes. The cartilages cultured for two weeks were implanted into growth plate defects of proximal tibiae of 6-weeks rabbits. At 4th and 16th weeks, X-ray, histologic and immunohistochemical examination were performed. Results　The tibiae had no marked deformities after 4 weeks of operation. Histologic examinations showed that the defects were filled with cartilage. Immunohistochemical results of type Ⅱ collagen were positive. The tibiae with allografts of cultured cartilages had no evident deformities after 16 weeks of operation. Histologic examination showed nearly closure of growth plates. On the contrary, the tibiae on control side formed severe deformities and growth plate were closed. Conclusion　Allograft of cultured cartilages into growth plate defects may replace lost growth plate tissues, maintain normal growth of limbs and prevent developmental deformity.

Objective　To study the feasibility of constructing tissue engineered cartilage by differentiated rabbit bone marrow mesenchymal stem cells(MSC) cultured in vitro and in vivo. Methods　The MSC were isolated from the nucleated cells fraction of autologous bone marrow by density gradient centrifuge, and then induced into chondrogenic differentiation by adding dexamethasone, transforming growth factor-β1(TGF-β1) and ascorbic acid in vitro. After 3 weeks, some cells turned to round shape and secreted metachromatic matrix. The cartilaginoid grafts composed of chondrogenic MSC. Bovine type Ⅰ collagen and human fibrin were cultured within the chondrogenic medium for 2 weeks in vitro or transplanted subcutaneously adjacent to the knee joint for 3 weeks in vivo. Results　The most cells in the grafts were degenerated and disappeared after cultured in vitro. But the residual cells were survival and secreted metachromatic staining proteoglycan with toluidine blue, which was characteristic cartilage matrix. The grafts developed into matured cartilage tissue assessed by histological examination after 3 weeks of transplantation in vivo. Conclusion　MSC can be used as functional cells to constructing tissue engineered cartilage.